Destination Mars
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2. Utopia Planitia—the “Nowhere Plain”—sounds like an odd translation to the modern ear. But the translation from the Greek is: oi (“not”) and topos (“place”) equating “nowhere.” So the modern association of a perfect society does not apply in this case.
3. The Viking sampler arm was an ingenious design. Rather than carry a heavy, pipelike arm (as later landers have indeed done), the Viking's arms were carried on a spool. It was designed like two giant metal tape measures affixed front-to-front to create an elliptical profile. As the flattened metal tape rolled off the spool, it sprang into the metal's memorized shape and became rigid. It could extend for over ten feet in this fashion and was strong enough to hoist small soil samples upward to the sample containers onboard. This also gave the arm an almost infinite sampling range across its entire length.
CHAPTER 11. DR. NORMAN HOROWITZ: LOOKING FOR LIFE
1. Dr. Norman Horowitz, interview by Rachel Prod'homme, July 1984, courtesy of the Caltech Archives, the California Institute of Technology.
CHAPTER 12. RETURN TO MARS: MARS GLOBAL SURVEYOR
1. After the loss of the space shuttle Challenger in 1986, spacecraft that required an upper stage boost to depart Earth orbit were, in general, rerouted to expendable rockets such as the Delta, Atlas, or Titan.
2. Hematite is a mineral that we will encounter in our Mars discussions again and again. It is a type of iron oxide, Fe2O3. It is harder than iron but more brittle. Important for Mars explorers, it is often found in areas that once hosted bodies of standing water, and it can condense out of water. It collects on the bottom of lakes and ponds, and it also can be found near hot springs. Alternatively, it can be found as a result of volcanic activity.
3. Great noises were made about the “Face on Mars” by some. While generally dismissed by the scientific community upon “discovery,” many wanted to believe—or hope—that it represented a message from an advanced civilization. Even when the improved images came in from MGS, some continued to support this belief. A few have made this into a cottage industry, and significant profits have resulted. This is currently a fringe industry at best.
4. In the words of JPL's internal review:
Mars Global Surveyor last communicated with Earth on Nov. 2, 2006. Within 11 hours, depleted batteries likely left the spacecraft unable to control its orientation.
“The loss of the spacecraft was the result of a series of events linked to a computer error made five months before the likely battery failure,” said board Chairperson Dolly Perkins, deputy director-technical of NASA Goddard Space Flight Center, Greenbelt, Md.
On Nov. 2, after the spacecraft was ordered to perform a routine adjustment of its solar panels, the spacecraft reported a series of alarms, but indicated that it had stabilized. That was its final transmission. Subsequently, the spacecraft reoriented to an angle that exposed one of two batteries carried on the spacecraft to direct sunlight. This caused the battery to overheat and ultimately led to the depletion of both batteries. Incorrect antenna pointing prevented the orbiter from telling controllers its status, and its programmed safety response did not include making sure the spacecraft orientation was thermally safe.
The board also concluded that the Mars Global Surveyor team followed existing procedures, but that procedures were insufficient to catch the errors that occurred. The board is finalizing recommendations to apply to other missions, such as conducting more thorough reviews of all non-routine changes to stored data before they are uploaded and to evaluate spacecraft contingency modes for risks of overheating.
“We are making an end-to-end review of all our missions to be sure that we apply the lessons learned from Mars Global Surveyor to all our ongoing missions,” said Fuk Li, Mars Exploration Program manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif.
Jet Propulsion Laboratory, news release no. 2007-040, JPL public affairs office.
CHAPTER 13. ROBERT BROOKS: IT TAKES A TEAM, MARS GLOBAL SURVEYOR
1. Robert Brooks, interview by the author, September 2011.
CHAPTER 14. ROVING MARS: SOJOURNER, THE PATHFINDER
1. From JPL's robotics section report on Pathfinder:
The Mobility and Robotic Systems section led the development of both software and electronics for the Sojourner rover. Software enabled autonomous control, sensing, and communication. Onboard autonomy consisted of simple behaviors for navigation, based on commanded objectives along with sensed terrain and vehicle position/ orientation. Terrain sensing was performed with cameras and laser striping, while Sojourner's position and orientation were measured by wheel odometry, accelerometers, and a z-axis angular-rate sensor. The onboard processor was a flight-qualified Intel 8085 running at 100 KIPS, and all software was written in C.
In addition to the onboard control software, section personnel developed the ground control software for the rover, and provided operations expertise during the 83-day mission. The rover visited 16 science locations, traversed more than 100 meters, captured more than 500 images, and nearly circumnavigated the lander. Due to the use of lander-based operations and the roughness of the terrain, all travel was effectively restricted to line-of-sight locations not greater than 12 meters from the lander. In addition to specification of targets and drive paths, regular corrections of vehicle position and attitude were provided by operators based on the lander imagery.
Jet Propulsion Laboratory, “Flight Projects—Pathfinder: Mars Pathfinder Rover: Sojourner,” Robotics, http://www-robotics.jpl.nasa.gov/projects/PATH.cfm?Project=4 (accessed September 2011).
CHAPTER 15. ROBERT MANNING, MARS PATHFINDER: BOUNCING TO MARS
1. Robert Manning, interview by the author, September 2011.
CHAPTER 16. MARS EXPRESS: ON THE FAST TRACK
1. As has been mentioned elsewhere in this book, the answer is not quite so simple. Of the many missions the Russians have dispatched to Mars (both as the Union of Soviet Socialist Republics and as the Russian Federation), a few have enjoyed partial success. In 1962, two years before Mariner 4, the Soviet Mars 1 relayed back some data but failed well before reaching Mars (it was a flyby mission). In 1971, Mars 2 (there had been many in between Mars 1 and 2, just with different naming schemes) successfully orbited Mars (just after Mariner 9 did the same). The craft operated and sent back data, but the Martian dust storm of that year made the data unrewarding. The lander piggybacked onto the mission crashed. Later in 1971, Mars 3 landed on the planet but operated on the surface for less than one minute. Mars 5 in 1973 entered orbit but failed shortly thereafter. Mars 6, a lander, sent back data on its way down to the surface but failed before landing. And so forth. The Russians have had much better luck with the exploration of Venus.
2. Mars 96 failed too. The Russian launch vehicle let the mission down; the fourth stage failed to reignite for a second burn.
3. For further information, see V. Formisano, S. Atreya, T. Encrenaz, N. Ignatiev, and M. Giuranna, “Detection of Methane in the Atmosphere of Mars,” Science 306, no. 5702 (2004): 1758–61.
4. As this book goes to press, NASA has just announced that, due to budget cuts, it will no longer be cooperating in the ExoMars mission.
CHAPTER 17. A LAUGH IN THE DARKNESS: THE GREAT GALACTIC GHOUL
1. “Uncovering the Secrets of Mars” (interview with Donna Shirley, former manager, JPL Mars Exploration Program), Time, July 4, 1997.
2. NASA/JPL online historical document, http://mars.jpl.nasa.gov/programmissions/missions/log/ (accessed January 27, 2012).
3. Jet Propulsion Laboratory Media Relations Office, press release, September 23, 1999, http://mars.jpl.nasa.gov/msp98/news/mco990923.html (accessed January 27, 2012).
4. Ibid.
5. Jet Propulsion Laboratory Media Relations Office, press release no. 99-134, November 10, 1999.
6. Jet Propulsion Laboratory Media Relations Office, press release no. 01-52, March 26, 2001.
7. Public Broadcasting Service, “NASA in Question,” Online NewsHour, April 14, 2000, http://
www.pbs.org/newshour/bb/science/jan-june00/nasa_4-14.html (accessed January 30, 2012).
CHAPTER 18. 2001: A MARS ODYSSEY
1. Or perhaps their own playbook. Up through Viking and until Mars Pathfinder and Mars Global Surveyor, most Mars-bound missions had been launched in pairs. When one US mission failed, as often occurred, the other always succeeded. The same conceit could be applied to systems internal to the spacecraft: hardware backups and twin units for redundancy.
CHAPTER 19. DR. JEFFREY PLAUT: FOLLOW THE WATER
1. Dr. Jeffrey Plaut, interview by the author, August 2011.
CHAPTER 20. TWINS OF MARS: SPIRIT AND OPPORTUNITY
1. “Sojourner's “rocker-bogie” mobility system was modified (from Pathfinder) for the Mars Exploration Rover Mission. To account for the extreme difference in weight and center of gravity from Sojourner, the mobility system on the Mars Exploration Rovers is in the back of the vehicle. The wheels are, naturally, larger and have evolved in design. Each wheel is approximately ten inches in diameter and has a unique spiral flecture pattern that connects the external part of the wheel with the spoke to absorb shock and prevent it from transferring to other parts of the rover. The rocker-bogie design allows the rover to go over obstacles (such as rocks) or through holes that are more than a wheel-diameter in size. Each wheel also has cleats, providing grip for climbing in soft sand and scrambling over rocks.” Jet Propulsion Laboratory, “In-situ Exploration and Sample Return: Autonomous Planetary Mobility,” http://marsrovers.nasa.gov/technology/is_autonomous_mobility.html (accessed September 2011).
CHAPTER 21. DR. STEVE SQUYRES AND THE MARS EXPLORATION ROVERS: DREAMS OF ICE AND SAND
1. Dr. Steven Squyres, interview by the author, August 2011.
CHAPTER 22. MARS IN HD: MARS RECONNAISSANCE ORBITER
1. For the sake of comparison: Deep Space 1 (comets) = 15 gigabits of data return, Mars Odyssey = 1012 gigabits, Mars Global Surveyor = 1759 gigabits, Cassini (Saturn) = 2550 gigabits, Magellan (Venus) = 3740 gigabits, and Mars Reconnaissance Orbiter = 34 terabits, or well over three times the others combined.
CHAPTER 23. DR. RICHARD ZUREK, MRO: I CAN SEE CLEARLY NOW…
1. Dr. Richard Zurek, interview by the author, August 2011.
CHAPTER 24. TWINS OF MARS: SPIRIT AND OPPORTUNITY, PART 2
1. The Antarctic volcano was, in turn, named after the HMS Erebus, an Arctic exploration vessel belonging to the British Royal Navy. And finally, this ship was named after the mythological dark regions of Hades (or hell) in Greek mythology.
CHAPTER 25. FROM THE ASHES, LIKE A PHOENIX
1. This was the first time such an arrangement had been tried to this degree. Plenty of missions had been run in cooperation with universities, but never had the actual mission control room been remotely located (landing was, as usual, handled at JPL). It was new territory—for both NASA/JPL and the University of Arizona. The university had to cobble together a control center, complete with high-speed internet connectivity, backups for both this and power supplies, and so forth. In the final analysis, it worked to the general satisfaction of the parties involved.
2. A commercial equivalent version of this chip came onto the market about 1991 in Macintosh® computers. But given the efficiency of the programming it was sufficient power for the missions it powered.
3. The Thermal and Evolved Gas Analyzer (TEGA) units work by receiving a sample of soil, sealing the covers, and baking the soil by slowly raising the temperature at a constant rate. The power used for heating is carefully tracked. The method is called scanning calorimetry and shows transitions from solid to liquid to gas of the components in the sample. At about 1800 degrees the ice in the sample vaporizes. This vapor travels to a mass spectrometer, which measures mass and concentrations at a molecular level. Organic molecules may be detected via this method.
CHAPTER 26. PETER SMITH: POLAR EXPLORER
1. Dr. Peter Smith, interview by the author, August 2011.
CHAPTER 27. MARS SCIENCE LABORATORY: BIGGER IS BETTER
1. This is one of NASA's last RTGs (Radioisotope Thermoelectric Generators). The space agency is running low on the fuel element, usually plutonium 238. This is one of the most toxic substances known to man and has been made in only very small quantities over the years. It was a nasty byproduct of the Cold War, and the two available stocks of the material, the United States and Russia, are just about out of it. When the United States ran low, it started buying it from Russia. But MSL will use a large chunk of the dwindling supply, and there is much hand-wringing in appropriate quarters about what will be done next. Any mission beyond Mars, and even some on that planet (as with MSL) require an RTG unit rather than solar panels. It's hard and expensive to make, and NASA does not have the funds to do so. Talks are under way with the Department of Energy to try to find a solution, but at this point, no answer is in sight.
2. Accelerometers have been used in rockets and spacecraft since the beginning of the space age for obvious reasons. Early on, their critical mission was to measure the acceleration of the rocket. Later they measured motion along other axes. And speaking of the iPhone®, in 2011, two of Apple's technological miracles were flown to the International Space Station and utilized for various experiments using, of course, a specially designed app.
CHAPTER 28. DR. JOY CRISP, MARS SCIENCE LABORATORY: DIG THIS
1. Dr. Joy Crisp, interview by the author, September 2011.
CHAPTER 29. JPL 2020: THE ONCE AND FUTURE MARS
1. ExoMars is being led by the European Space Agency with collaboration with NASA and there will probably be others. It has been through a few iterations, but at its core is an orbiter that will search for trace gases is the atmosphere and a lander for somewhere around 2016, and a possible rover for 2018. The trace-gas orbiter is searching primarily for methane, as the Mars Express mission has detected the gas in the Martian atmosphere, indicating geological activity and, possibly, life.
2. The official reason for the cancellation of the Scout program was that as operations at Mars were increasingly focused on the surface of the planet, the $500 million budget cap for Scout missions would not be able to fund a reliable lander.
CHAPTER 30. MARS ON EARTH
1. Irene Klotz, “Viking Found Organics on Mars, Experiment Confirms,” Discovery News, January 4, 2011.
2. Also called drainage wind, these strong winds occur when a higher-density air mass flows down a hill or slope to a lower-density area. They can range from a few miles per hour to hurricane force. As they descend and compress, heating can occur as the mass is concentrated. In the Antarctic, the air stays cold.
3. “Antarctic Expedition Prepared Researchers for Mars Project,” NASA/JPL press release, February 2009, http://www.jpl.nasa.gov/news/features.cfm?feature=2017 (accessed October 2011).
CHAPTER 31. THE NEW MARTIANS
1. Robert Manning, interview by the author, September 2011.
2. Dr. Chris McKay, interview by the author, October 2011.
3. Dr. Robert Zubrin, interview by the author, October 2011.
Ezell, Edward Clinton, and Linda Neumann Ezell. On Mars. New York: Dover, 2009.
Godwin, Robert. Mars: The NASA Mission Reports. Vols. 1-2. Ontario: Apogee Books, 2000.
Kessler, Andrew. Martian Summer. New York: Pegasus Books, 2011.
Lowell, Percival. Mars. Cheshire, England: New Line Publishing, 2009. First published in 1897, in New York, by Houghton Mifflin.
——. Mars as the Abode of Life. Boston: Adamant Media, 2002. First published in 1898, in London, by Smith, Elder.
Maimone, Mark, P. Charles Leger, and Jeffrey Biesiadecki. Overview of the Mars Exploration Rovers' Autonomous Mobility and Vision Capabilities. Washington, DC: National Aeronautics and Space Administration (NASA)/Jet Propulsion Laboratory (JPL), 2007.
Morton, Oliver. Mapping Mars. New York: Picador/MacMillan, 2002.
National Aeronautics and Space Administration (NASA)/Jet Propulsion Laboratory (JPL). “JPL Technical Memorandum no. 33-229.�
�� In To Mars: The Odyssey of Mariner IV. Washington, DC: NASA/Caltech, 1965.
——. Mars Climate Orbiter Press Kit. Washington, DC: NASA/JPL,1999.
——. Mars Global Surveyor (MGS) Loss of Contact. Washington, DC: NASA/JPL, 2007.
——. Mars Reconnaissance Orbiter Press Kit. Washington, DC: NASA/JPL, 2006.
——. Mars Science Laboratory Radiological Contingency Planning. Washington, DC: NASA/JPL, 2010.
——. NASA Facts: Mars Global Surveyor. Washington, DC: NASA/JPL, 2000.
——. NASA Facts: Mars Pathfinder, 5-99AS. Washington, DC: NASA/JPL, 1999.
——. NASA Facts: Mars Reconnaissance Orbiter. Washington, DC: NASA/JPL, 2006.
——. NASA Facts: Mars Science Laboratory 2011. Washington, DC: NASA/JPL, 2011.
——. NASA Facts: The Viking Mission. Washington, DC: NASA/JPL, 1975.
——. NASA Facts 2001: Mars Odyssey 2003. Washington, DC: NASA/JPL, 2003.
——. “Release 71-215.” In Mariner 9 Press Kit. Washington, DC: NASA/JPL, 1971.
Nicks, Oran. A Review of Mariner 4 Results, NASA SP-130. Washington, DC: National Aeronautics and Space Administration (NASA)/Jet Propulsion Laboratory (JPL), 1967.
Turner, Martin. Expedition Mars. New York: Springer-Praxis, 2004.
Wilson, James. Two Over Mars: Mariner 6 and Mariner 7. Washington, DC: National Aeronautics and Space Administration (NASA)/Jet Propulsion Laboratory (JPL), 1969.